docs: def get_child_models(self):
          """
          Get child models from registered plugins. Fallback to the child model
          admin and its base model if no plugins are registered.
          """
          child_models = []
          for plugin in self.child_model_plugin_class.get_plugins():
              child_models.append((plugin.model, plugin.model_admin))
          if not child_models:
              child_models.append((
                  self.child_model_admin.base_model,
                  self.child_model_admin,
              ))
          return child_models